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At least 883 records · Page 49Linked to original sources
arXiv2013

Modeling of the long-time asymptotic dynamics of a point-like object

We introduce four original concepts: First, the point-like object (PO) specified as a classical extended real object whose response to an external force is aptly specified solely by the trajectory of a single point, whose velocity eventually stops changing after the cessation of the external force. Second, the dynamic models of an PO that generalize the Newton second law by the explicit modeling of PO-acceleration by nonlinear functions of the external force. Third, the long-time asymptotic dynamics of an PO (LTAD) modeled by polynomials in time-derivatives of the external force (by LTAD-models). To make LTAD-models we do not need to know the PO equation of motion. Given the PO equation of motion, without solving it, we can calculate the appropriate LTAD-models, but not vice verse. Fourth, the asymptotic differential equations about the LTAD. They are equivalent to the LTAD-models, but not to the PO equation of motion. To resolve the conceptual controversy surrounding the relativistic Lorentz-Abraham-Dirac equation, we interpret this equation as an asymptotic differential equation about the LTAD of an electrified PO, and not as a differential equation of motion for an electrified PO. Keywords: Point-like; asymptotic dynamics; cyclic motion; differential equation; Lorentz-Abraham-Dirac equation

physics.gen-ph↗
arXiv2012

The second law of thermodynamics can never be violated for all time- and space-scales

Maxwell's demon was created with abilities to violate the second law of thermodynamics. But the demon always fell short of doing so because of the imposed restrictive condition that reads, the demon needs to do "work". Therefore, you can always preserve the second law by default. Here, we encounter the supernatural demon (without the above restriction) right at the melting point, and unambiguously expose why the demon is still doomed to fail for all time- and space-scales. This means that the second law of thermodynamics can never be violated. We develop an analytic strategy (based on Newton's third law) to properly analyze the entropy in a chemical system with respect to forward and reverse trajectories. We also explain the physico-chemical processes that are responsible at very short timescales.

physics.gen-ph↗
arXiv2012

A beacon of new physics: The Pioneer anomaly modelled as a path based speed loss driven by the externalisation of aggregate non-inertial QM energy

This treatise outlines how a non-systematic based Pioneer anomaly, with its implied violation (re: 'low' mass bodies only) of both general relativity's weak equivalence principle and the Newtonian inverse-square law, can be successfully modelled. These theoretical hurdles and various awkward observational constraints, such as the low value of Pioneer 11's anomaly pre-Saturn encounter, have (to date) not been convincingly modelled. Notwithstanding the recent trend to embrace a non-constant Sun/Earth-directed heat based explanation of this anomalous deceleration, the actual: nature, direction, and temporal and spatial variation of the Pioneer anomaly remain an open arena of research. Working backwards from the observational evidence, and rethinking: time, mass, quantum entanglement and non-locality, we hypothesise a mechanism involving a quantum mechanical energy source and a new type of 'gravitational' field; neither of which lie within general relativity's domain of formulation/application. By way of a systemic conservation of energy principle, an internally inexpressible (aggregate) non-inertial energy discrepancy/uncertainty -- involving a myriad of quantum (lunar/third-body residing) atomic and molecular systems moving in analog curved spacetime -- is (non-locally) re-expressed externally as a (rotating) non-Euclidean spatial geometry perturbation. At a moving body each "rotating space-warp" induces sinusoidal proper acceleration and speed perturbations, as well as a path-based constant (per cycle) rate of speed shortfall relative to predictions that omit the additional effect. 'Solutions' of the new model may extend to: the Earth flyby anomaly, solar system related large-scale anomalies in the CMB radiation data, the nature of dark energy, and how a theory of everything unification agenda is inadvertently impeding a deeper understanding of physical reality and quantum entanglement.

physics.gen-ph↗
arXiv2013

Gravitomagnetic forces and quadrupole gravitational radiation from special relativity

The mere principle of relativity and Lorentz transformations for the mass current predict, in close analogy to electromagnetism, the existence of gravitomagnetic fields. With the reasonable assumption of the non existence of a gravitomagnetic mass, a parameter-free set of equations for "effective" vector gravitoelectromagnetism results. As a consequence gravity propagates at the speed of light in a flat Minkowski space and quadrupole gravitational radiation, consistent with energy balance, is predicted with the same value of GR. Heuristic considerations relate gravitational radiation to the strong field parameter $\frac {GM}{c^2 r}$, suggesting the complete evaporation of a black hole at the Planck scale.

physics.gen-ph↗
arXiv2014

A Direct Inspection of the Displacement Current Using the Phase Measurement

After J. C. Maxwell brought forward the concept of displacement currents, H. R. Hertz and other scholars verified the existence of electromagnetic waves in experimental, and then confirmed indirectly the conceptive correctness of displacement currents. During the recent years, along with the evolution of electronic measurement technologies, the researchers are attempting to validate directly the amplitude and orientation of displacement currents in experimental. The paper proposes and achieves one phase measurement experiment to scrutinize the orientation of displacement currents. The study indicates that the existing measurement technology is capable of inspecting directly the amplitude and orientation of displacement currents. The test results do not locate on the predicted range of classical electromagnetic theory presently. The displacement current may not be treatable similar to the conductive current to a certain extent. This conclusion enriches the understanding to the property of displacement currents.

physics.gen-ph↗
arXiv2012

Scalar Field Theory on Supermanifolds

In this paper we will analyse a scalar field theory on a spacetime with noncommutative and non-anticommutative coordinates. This will be done using supermanifold formalism. We will also analyse its quantization in path integral formalism.

physics.gen-ph↗
arXiv2013

Transistor as a Rectifier

Transistor is a three terminal semiconductor device normally used as an amplifier or as a switch. Here the alternating current (a.c) rectifying property of the transistor is considered. The ordinary silicon diode exhibits a voltage drop of ~0.6V across its terminals. In this article it is shown that the transistor can be used to build a diode or rectify low current a.c (~mA) with a voltage drop of ~0.03V. This voltage is ~20 times smaller than the silicon diode. This article gives the half-wave and full-wave transistor rectifier configurations along with some applications to justify their usefulness.

physics.gen-ph↗
arXiv2012

Extended Equivalence Principle: Implications for Gravity, Geometry and Thermodynamics

The equivalence principle was formulated by Einstein in an attempt to extend the concept of inertial frames to accelerated frames, thereby bringing in gravity. In recent decades, it has been realised that gravity is linked not only with geometry of space-time but also with thermodynamics especially in connection with black hole horizons, vacuum fluctuations, dark energy, etc. In this work we look at how the equivalence principle manifests itself in these different situations where we have strong gravitational fields. In recent years the generalised uncertainty principle has been invoked to connect gravity and curvature with quantum physics and now we may also need an extended equivalence principle to connect quantum theory with gravity.

physics.gen-ph↗
arXiv2012

Gauge Theory on a Four Sphere

In this paper we will analyze the quantization of a gauge theory on a four sphere. This will be done by mode expanding all the fields in the theory in terms of harmonic modes. We will also analyse the BRST symmetry of this theory.

physics.gen-ph↗
arXiv2012

Resolution of the Mansuripur Paradox

The interaction of a magnetic dipole with a point charge leads to an apparent paradox when analyzed using the 3-vector formulation of the Lorentz force. Specifically, the dipole is subject to a torque in some frames and not in others. We show that when analyzed according to the covariant 4-vector formulation the paradox disappears. The torque that arises in certain frames is connected to the time-space components of the torque in the rest frame, giving rise to "hidden" momentum.

physics.gen-ph↗
arXiv2012

An angle to tackle the neutrinos

A brief history of the discovery of neutrino oscillations and neutrino mass is presented highlighting the recent breakthrough in the determination of a crucial neutrino parameter by the Daya Bay and RENO reactor experiments. The importance of this parameter in the context of one of the goals of the India-based Neutrino Observatory (INO) project and also in advancing the frontier of neutrino physics is explained.

physics.gen-ph↗
arXiv2012

One-Way Speed of Light Measurements Without Clock Synchronisation

The 1991 DeWitte double one-way 1st order in v/c experiment successfully measured the anisotropy of the speed of light using clocks at each end of the RF coaxial cables. However Spavieri et al., Physics Letters A (2012), doi: 10.1016/j.physleta_2012.0010, have reported that (i) clock effects caused by clock transport should be included, and (ii) that this additional effect cancels the one-way light speed timing effect, implying that one-way light speed experiments "do not actually lead to the measurement of the one-way speed of light or determination of the absolute velocity of the preferred frame". Here we explain that the Spavieri et al. derivation makes an assumption that is not always valid: that the propagation is subject to the usual Fresnel drag effect, which is not the case for RF coaxial cables. As well DeWitte did take account of the clock transport effect. The Spavieri et al. paper has prompted this clarification of these issues.

physics.gen-ph↗
arXiv2019

Non-Uniqueness of the Lienard-Wiechert Potential

The Lienard-Wiechert potential is one of the central equations of classical electrodynamics. Among its properties are these: it satisfies the (linear) homogeneous wave equation and Lorenz Gauge condition in free space, it varies inversely with distance from the classical point-source that is movong arbitrarily, and its effects propagate along straight lines at constant speed (the speed of light). Do any other retarded potentials satisfy these properties? It is shown here that other such potentials do exist, and a general formula is derived.

physics.gen-ph↗
arXiv2012

Virtual Particle Interpretation of Quantum Mechanics - a non-dualistic model of QM with a natural probability interpretation

An interpretation of non-relativistic quantum mechanics is presented in the spirit of Erwin Madelung's hydrodynamic formulation of QM and Louis de Broglie's and David Bohm's pilot wave models. The aims of the approach are as follows: 1) to have a clear ontology for QM, 2) to describe QM in a causal way, 3) to get rid of the wave-particle dualism in pilot wave theories, 4) to provide a theoretical framework for describing creation and annihilation of particles, and 5) to provide a possible connection between particle QM and virtual particles in QFT. These goals are achieved, if the wave function is replaced by a fluid of so called virtual particles. It is also assumed that in this fluid of virtual particles exist a few real particles and that only these real particles can be directly observed. This has relevance for the measurement problem in QM and it is found that quantum probabilities arise in a very natural way from the structure of the theory. The model presented here is very similar to a recent computational model of quantum physics and recent Bohmian models of QFT.

physics.gen-ph↗
arXiv2012

On the Lamb vector divergence, evolution of pressure fields and Navier-Stokes regularity

This paper analyzes the Lamb vector divergence, also called the hydrodynamic charge density, and its implications to the Navier-Stokes system. It is shown that the pressure field can be always chosen in a way that ensures regularity of the Navier-Stokes system. The abstract pressure field that ensures regularity is defined through two partial differential equations, being of the elliptic kind. The pressure field defined such a way can be interpreted as a control potential field that keeps the system regular. The controlling pressure field depends only on the velocity field of the fluid and its derivatives, so that the result is applicable in any general setting where the initial data is divergence free, smooth and square-integrable.

physics.gen-ph↗
arXiv2013

Gravity of R^{ik}=0: A New Paradigm in GR

Theory of general relativity (GR) has been scrutinized by experts for almost a century and describes accurately all gravitational phenomena ranging from the solar system to the universe. However, this success is achieved provided one admits three completely independent new components in the energy-stress tensor $T^{μν}$$-$inflaton, dark matter and dark energy, which though do not have any non-gravitational or laboratory evidence and have remained generally speculative. Moreover, the dark energy poses a serious confrontation between fundamental physics and cosmology. The present situation reminds us of Einstein's `biggest blunder' when he forced his theory to predict a static universe, perhaps guided by his religious conviction that the universe must be eternal and unchanging. It seems that we are making a similar blunder by forcing $T^{μν}$ into the field equations while the observations indicate that it is not needed. We seem to have a deep-rooted conviction that the spacetime will remain empty unless we fill it by the energy-stress tensor. However, we have been ignoring numerous evidences earnestly indicating otherwise. From a critical analysis of the present situation, we develop an entirely new insight about the source of curvature in equations $R^{μν}=0$ which, though may appear orthogonal to the usual understanding, is in striking agreement with all known phenomena in GR. Moreover, it answers some hitherto unexplained puzzles and circumvents some long-standing problems of the standard paradigm.

physics.gen-ph↗
arXiv2013

The Machian contribution of the Universe to geodetic precession, frame dragging and gravitational clock effect

Gravitomagnetism resulting from SR has been applied to geodetic precession and frame dragging. The substantial contribution of the "fictitious" Coriolis force, due to the relative rotation of the rest of the Universe in the non inertial frame of the free falling but rotating satellite, has to be taken into account, giving another quantitative confirmation of Mach's arguments and of the black hole nature of our Universe. Also the gravitational clock effect has an elementary prediction in the present post Newtonian formulation. A derivation of the centrifugal force from an effective vector formulation of gravitation is attempted. The centrifugal force appears to be due to a relativistic effect of the counter-rotating Universe. Gravitomagnetic energy effects, a million times stronger than the self energy effects responsible for curvature in the GR language, would thus produce the centrifugal acceleration. The Machian picture, already successful in the case of the Coriolis force, gets an additional circumstantial support.

physics.gen-ph↗